On my 1984 Station wagon, the upper van side seals are LR053839 (Left) and LR053838 (Right). These are not interchangeable (sided).
Regarding the lower seals:
I've attached the part numbers of the defender lower van side waist seals. Note that there are a lot of numbers and none are cheap.
On my truck, which is a 1984, Mike (my truck's PO) used PN 333487, which is the Series lower seal and in addition to being cheaper, is also non-sided, meaning you can use the same part for both left and right.